AW: always show menu

This always shows the icon on L-M (because "report a bug" is still
useful), and just hides the "switch WebView provider" menu option.

Bug: 1070306
Test: Manual - launch on L-M and verify menu has "report bug" option
Change-Id: I6baf14fcaa39d1f76decdb3214d2414d779b0750
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2147871Reviewed-by: Richard Coles <torne@chromium.org>
Commit-Queue: Nate Fischer <ntfschr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#758608}

android_webview/nonembedded/java/src/org/chromium/android_webview/devui/MainActivity.java

@@ -156,8 +156,11 @@ public class MainActivity extends FragmentActivity {
 
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
         getMenuInflater().inflate(R.menu.options_menu, menu);
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N) {
+            // Switching WebView providers is only possible for API >= 24.
+            MenuItem item = menu.findItem(R.id.options_menu_switch_provider);
+            item.setVisible(false);
         }
         return true;
     }